UltraFire 18650 3.7V Rechargeable SJ Battery 6000mAh Blue RECHARGEABLE 3.7 V 18650 6000mAh li-ion Battery 6000mAh 3.7V 18650 rechargeable Battery No memory effect, recharge up to 1000 cycles 100% quality Japanese battery cells 100% Q.C. of every battery Manufactured by Hi-Capacity power products.